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The
nutrient files: vitamin A is out there
By
Anna Niec
Nutritionist
This is the first of a series of articles that will focus on nutrients.
Nutrients
are naturally present in foods or synthetically produced in laboratories.
The
best source of nutrients is fresh food.
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Recommended
Dietary Intakes
Vitamin A Pro-vitamin A
Men 19-64 750mcg
Women 19-54 750mcg
Best sources LIver, eggs, yellow fruit and mature cheese,
and vegies
butter, margarine,
Intake one serve a day two serves
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Scientists
are not able to replicate the entire set of nutrients found in nature
and many more may still be discovered.
Nutrients
are essential to the maintenance of good health.
Lack
of minerals and/or vitamins in our diet will eventually result in
compromised health, for example, more frequent colds, lower energy
levels and poor skin.
In
Australia, we are able to eat a varied, nutritionally balanced diet
which provides us with all the nutrients we need to remain in good
shape.
Unfortunately,
we are often relying on too many processed meals or snacks which
are high in calories but nutritionally poor.
My
aim in writing the nutrient files is to introduce each of the essential
vitamins and minerals and explain how to make sure we eat each of
the nutrients in sufficient amounts to ensure good health.
Vitamin
A
Vitamin A is one of the four fat-soluble vitamins. It is essential
for good eyesight and a robust immunity.
The
human body can make vitamin A from a group of plant molecules called
carotenoids.
These
are turned into active vitamin A following their absorption.
Carotenoids
are found in yellow/orange coloured fruits and vegetables as well
as dark leafy vegetables.
Vitamin
A deficiency is rare in Australia.
The
amount of vitamin A can, however, be marginal in a very low fat
diet.
Those
of you who are serious about your physique and fitness level and
follow a low fat diet, peruse the table shown to check whether or
not you are consuming a sufficient amount of vitamin A.
If
you smoke, your requirements for vitamin A rise.
Many
of the toxic chemicals present in cigarette smoke, once inhaled,
damage healthy cells in the lungs.
Vitamin
A has been shown to help strengthen the epithelial cells that are
the first point of contact with inhaled smoke inside the lungs.
The
recommended amounts of vitamin A, together with its best food sources,
including excellent food sources of pro-vitamin A, are listed in
the table below.
To
prevent losses of vitamin A in food preparation dont fry foods
too often temperatures above 100 degrees celsius increase
vitamin A loss.
Also
avoid leaving foods exposed to air for long periods of time.
If
you suspect that you may be eating too little vitamin A, dont
be tempted to reach out for a supplement.
Taking
vitamin A in large doses or for a long period of time may result
in vitamin A toxicity.
If
you already take a vitamin supplement, please ensure that you are
not taking vitamin A in amounts over the safe upper limit which
is 3000 mcg daily.
Generally,
vitamin A supplements should not exceed the daily RDI (Recommended
Dietary Intake).
- Next
in the nutrient files: Be in tune with the Bs.
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